Abstract
Avian infectious bronchitis virus grownin ovo was purified by differential centrifugation and isopycnic sedimentation in density gradients. The purified virus was analysed by SDS polyacrylamide gel electrophoresis and found to comprise up to sixteen polypeptides, four of which were glycopeptides. Bromelain treatment of the particles removed three polypeptides and two glycopeptides.